Organic field-effect transistor is a semiconductor device that employs an organic semiconductor material to replace the traditional silicon semiconductor material as the active layer, and it may be applied to the field of flexible displays.
Organic semiconductor materials that may be used for manufacturing an active layer include: metal complex-type, polymer-type, hybridized type and micromolecule-type materials. Preferably, the organic semiconductor material for the active layer of an organic field-effect transistor is a micromolecule-type material, and more preferably, pentacene. This is because that, when pentacene is employed in place of silicon semiconductor material as an active layer, the mobility of the organic field-effect transistor may reach or even exceed the mobility of the transistor that employs traditional silicon semiconductor material as an active layer.
At present, a pentacene layer that functions as an active layer is generally manufactured by a wet process of printing a pentacene precursor and then heating directly. However, since a solvent may volatilize during the wet process, a coffee ring may be formed on the pentacene layer, so that the optical property of an organic field-effect transistor that includes the pentacene layer will be influenced. In addition, the presence of the solvent makes the pentacene layer have flowability, thus the size and shape of the pentacene layer prepared will be changed, and the precision of the active layer will be influenced.
During experiments, the inventors find that, if a photoetching process is employed to form the pentacene layer, the above problem may be overcome. But at present, the pentacene precursor does not contain ultraviolet reactive groups, thus the pentacene layer cannot be prepared by a photoetching process.